While I do carry a spare battery for my Palm Pre (s palm), I can’t do that with my iPhone 3GS (s aapl). For $20 though, I might address that problem by picking up one of the Duracell Instant Chargers that earned rave reviews at Giz. Duracell actually has a line of three chargers that can power portable devices: the Instant, the Powerhouse and the Pocket Charger. Each stores energy during a charge cycle from an electrical outlet, or can be charged from your computer.
The Pocket Charger looks the most portable, but it’s also the most limited — it only stores 500mAh of power and works with Mini-USB devices. The $20 Instant and $50 Powerhouse both hold four times the energy and support USB devices as well as Mini-USB, so they’re usable with more gadgets. The larger Powerhouse can charge two devices at one time, but I can’t think of a solitary instance where I needed that function. I also don’t need the larger bulk, so the “nearly weightless” Instant model ought to do the trick.
There’s a number of iPhone-friendly charging cases and solutions out there — we put two in the ring together last year — but they’re generally specific to the iPhone. When I look for a mobile technology solution, I try to find the most generic solution that still fits my needs. That’s why I’ve always used a USB adapter for my 3G plans and that’s why I’ll take one of these Duracell chargers over a device-specific solution. Well, I’ll get one after they appear online — Amazon shows the device, but says they’ll notify me when it becomes available.